Mark B

Mark B

I was born in Denver, raised in New England, and have had the good fortune to live in many places across the globe for work, study and the Peace Corps. No matter where I’ve lived, there has always been the need for three constants: food, shelter and water. It’s water that has always interested me - whether it is water for drinking, aquaculture or hydroponics; sailing over or exploring under the surfaces of oceans and lakes; or even the way some plants have evolved to collect mist and dew in places they could not otherwise survive. These days, it is the increasing scarcity of water suitable for drinking – for our very survival – that inspires me most. As a Research Scientist, working at Kinetico for 12 years, I’ve been able to take my passion for and knowledge about water and share it with others to help create clean water solutions.

Water Contaminant: Lead

by Mark B Published 11.4.2015

You’ve probably already heard that Lead is a toxic metal that you don’t want in your drinking water.  Interestingly, the connection between Lead and water delivery goes back to at least Roman times.   In fact, the Latin word for Lead is plumbum, which gives us the chemical symbol Pb, as well as the words “plumbing,” “plumber,” etc.  In spite of how useful it has always been, Lead also causes significant health issues.  Consuming Lead has been shown to reduce intelligence, increase aggression, cause deafness, stunt growth, and damage organs including the brain and kidneys.  Children are at greatest risk because they are growing and because of their smaller bodies (they would consume more relative to their body weight).  The USEPA regulates Lead in public water supplies to a maximum of 0.015 parts per million, but the public health goal is to have zero in drinking water.   


Typically Lead would be present because it leached from Lead pipes or joints that bring water into the house, leached from Lead solder used to join pipes together, or from erosion of natural ores in the ground.  Another source could be older brass faucets or other fittings which come in contact with the water.  While Lead has been banned from plumbing solder and distribution system piping for many years, just recently the US EPA determined that only brass with less than 0.25% Lead content is allowed to be in contact with drinking water.

This metal can be either dissolved in the water or it may be present as very small particles, or it  can be in both forms at the same time.  When treating your water in the home it is important to  be aware of this.  A filter that reduces one form may not do a good job with the other.  For example,  a pitcher might do well against dissolved Lead but not particulate, while a micron cartridge might filter some particles but not the dissolved form.  To protect yourself and your family, choose a treatment that has been certified to the relevant standard.  Because of normal shifts in water chemistry or physical disturbances to pipes, it may be best to select a device that reduces both forms of Lead.  Point-of-use choices include reverse osmosis, distillation, as well as carbon blocks that have been specially designed to treat both the particulate and dissolved forms of Lead.  The web sites of the Water Quality Association and National Sanitation Foundation provide listings of devices certified to Standards WQAS-200, ANSI/NSF 53, 58, 62, and 372.   

It’s probably worth having your water tested, especially if you have children and / or live in an older home.  Lead in drinking water can be a serious health hazard.  Fortunately there are many options to limit exposure for you and your family.

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The Water Conditions in Ethiopia, Part Two

by Mark B Published 9.24.2015

While in Ethiopia in August to learn more about what they do about drinking water, I visited the Debre Damo Monastery.  About 1,600 years old, it is situated on a flat-topped outcropping of solid rock. The only way in or out is by climbing a sheer cliff using a 15 meter rope made from woven rawhide. The top supports a community of about 150 monks. Certainly the most extreme location I found people living in this most northern part of the country. Tufts of green in the landscape below reminded me that it was still their short rainy season.    


The question in my mind is that these men live on top of a solid piece of rock - what do they do for drinking water? The site has been in constant use for centuries, so they must have solved this essential question long ago. The answer is found in the rain catchment pools carved into the stone itself.


Although many consider the water here to be holy, the source is vulnerable to pollution. The pools are open to the sky so bird droppings can fall in, a resident troupe of monkeys use the same water source, and anything that lands on the bare rock surrounding the pools can be blown or washed in. The abundance of algae on the surfaces is an indication that nutrients are present. (Algae could easily be transported to this place on the legs of birds.) The water I sampled was positive for coliform bacteria. 

It would be interesting to return in the dry season. If I go again I now know to bring a wider range of water test kits. I would like to check water quality when contaminants are likely to be more concentrated due to evaporation.  Time and opportunity did not permit on this visit, but it would be interesting to talk to the monks about their perceptions of drinking water quality. Is there any evidence of illness caused by this water? Are they interested in treating it or even reducing evaporation? Maybe not. There were some very old men up there. Perhaps in this case the habits and traditions of centuries are as sustaining as the water itself. 


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The Water Conditions in Ethiopia, Part One

by Mark B Published 8.26.2015

In August, I was able to visit northern Ethiopia to look at some of the drinking water issues.  As you might guess, there are many, ranging from polluted water to almost no water at all.  That made it interesting to discover the inhabitants of Adwa and Aksum rely on a reservoir.  The reservoir water is treated first by aeration to oxidize iron, then with a flocculant which attracts dirt like a magnet, slow sand filtration to remove the floc, and finally chlorination to disinfect.  This level of treatment is actually standard practice for many municipalities in more developed countries.   

 I brought with me a kit to test for coliform bacteria – the kind of bacteria normal to the human gut.  Most are not harmful, but you probably have heard of a bad one that  represents fecal coliforms: E. coli.  I tested multiple faucets where I was staying in Adwa and found no coliforms at that moment in time, including no E. coli.  This water is typically provided by a single tap to a group of households.  It is relatively unusual for Ethiopians to have fairly easy access to water, so what I observed might be considered a model for “best practices” in the country. 


Outside Adwa and Aksum, however, the situation was more like what I was expecting, which is to say dire. With the help of a guide, my two Kinetico co-workers and I took a half hour ride out of Adwa to Gendebta. As we hiked along paths through farm fields, we first passed a hand dug well and a manually pumped well, then another manually pumped well, and finally came to a muddy hole that water seeps up into. 

The first pump did not work, so the hand dug well was being used for livestock and humans to drink from. It tested positive for total coliforms and E. coli. Further away, the second pump did produce water, but only during the very short rainy season. 

The photo shows a barefoot girl filling and carrying a 20-liter container for her family.  The jerrycan is carried using a length of rope across her chest. While her journey home that day was fairly short, that water still weighs about 44 pounds.

After hiking for an hour, we came to the source of water people use when the shallow wells no longer produce.  As I watched, a mother and daughter filled their clay water jugs, skimming the less muddy water from the top. Livestock stand in the puddle to drink from it as well. In the 10 month dry season people travel by foot over great distances to collect their water here. They collect water early in the morning until it runs out. Then they wait until the afternoon when it has refilled a bit. This source tested positive for coliforms. 

While the people of Adwa and Aksum are fortunate to have a year-round source of water that is relatively safe to use, most of the country does not.  Those who collect for their households are primarily girls and women travelling long distances to carry heavy loads, perhaps more than once a day. 

When I returned home and opened the tap, I just stared for a moment, appreciating what I have and thinking further about how I can help. 


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Disinfecting Your Water

by Mark B Published 5.13.2015

In 1854 there was an outbreak of cholera in London. A doctor named John Snow was very intent on finding out the source of what was killing people. He went door to door to map out household deaths, and determined that what everyone had in common was they had all drawn water from the same community pump on Broad Street. Legend has it that he took the handle off the pump to stop its use. It was then found that this particular pump was drawing water contaminated with the city's waste. It can be argued that John Snow was the father of what we now know as modern Public Health.

Woman Filling a Glass

A major triumph of civilization is our ability to treat drinking water to prevent water borne diseases. This is the single most important factor in lengthening human life expectancy. Take a look at some waterworks built starting in the late 1800's. Many were built from stone, contain polished brass and bronze fixtures, and were meant to serve as lasting monuments to a community's commitment to the health of its citizens. Sand filtration and the addition of chlorine are common methods used to remove or kill microbes in the water supply. Sadly, cholera still causes illness and death in the world today because so many people still don't have access to even these basic tools.

Clean drinking water is easy to take for granted when you, your parents and grandparents have all lived with it. Without chlorine or chloramine added to our water supply, our world would be a very different place indeed. A friend of mine says he likes the smell of chlorine in his drinking water because then he "knows it's working." But for many of us the taste and odor of disinfectants can be disagreeable. We like being protected, but prefer not to drink it. Fortunately, this is one of the easiest things to treat. Activated carbon is most commonly used in a tank for the whole house or a cartridge at the point of use. Carbon removes chlorine, chloramine and a number of contaminants by a process called adsorption, which is kind of like how dirt is held onto sticky tape. Standard activated carbon works great for chlorine reduction, but catalytic activated carbon is better for chloramine. Carbon has a finite life span and needs to be replaced periodically. How often it is replaced mostly depends on how much water has been used and how much chlorine or chloramine needed to be removed.

So eat, drink, and be merry, for you have safe water today and tomorrow, and it can taste good too.

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Cyanobacteria (aka "Blue Green Algae") and Microcystins

by Mark B Published 8.14.2014

Recently nearly half a million people using Lake Erie for drinking water were warned not to use it. The reason for this is increasingly common in Lake Erie and other surface waters. By the time fall and late summer have rolled around, enough excess nutrients have washed into our waterways that the natural balance can be upset. 

In particular, cyanobacteria – also known as “blue green algae” – are given the ideal opportunity (temperature, sunlight, and nutrients) to outcompete other waterborne organisms to create a vast, green soup that can be dangerous to drink or even bathe in. Harmful algal blooms have also been associated with the death of pets and livestock. In the case of that corner of Lake Erie which serves Toledo and the surrounding communities, toxins called microcystins were found to be present in the water going to people’s homes even after going through the treatment plant. There are many kinds of cyanobacteria that produce at least 80 different microcystins. Other cyanobacteria produce different toxins, such as anatoxins, saxitoxins, and cylindrospermopsin. Microcystins are held in the cell wall of the cyanobacteria, and when the cells break open, the toxins are released. While the US EPA still has no official limit, the World Health Organization recommends just 1 part per billion for microcystins in drinking water. People who consume the water can have rapid liver damage and risk cancer from long term use. Microcystins may also irritate the skin and eyes of people who bathe in just a few parts per billion.
Public water providers are normally very good at dealing with the seasonal challenges of these blooms.  Municipalities at risk test regularly, but this year weather conditions may have conspired to catch them off guard. Recent news reports advise that NASA will now use its satellites to help monitor the lake.

NOAA Great Lakes CoastWatch Lake Erie

NOAA Great Lakes CoastWatch Lake Erie 8-4-2014

It has been found that certain oxidants, such as potassium permanganate (KMnO4), are very useful to not only destroy the cell, but break down the microcystin molecules themselves. In addition, powdered activated carbon may be used since its high surface area and high adsorbency allows it to rapidly soak up the toxins. Microcystins have a molecular weight around 1,000 Daltons, which is probably why reverse osmosis membranes have been shown to be effective. Laboratory testing is critical to ensure that the treatment of any cyanotoxin is effective. 

Although lawns and leaky septic tanks can contribute to this extremely serious problem, there is very strong evidence attributing algal blooms mainly to agricultural fertilizers, perhaps because they are applied at the wrong times or in too great amounts. Life has a natural balance and the cause of harmful algal blooms is preventable. Is it worth getting this extremely important problem under control? Just ask the half million people who spent a few days unable to drink from their faucets, yet live next to the greatest fresh water resource on earth. 

Additional Information:


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Water Contaminant: Nitrates

by Mark B Published 6.4.2014
Diagram of a nitrate molecule

Nitrate is the anionic part of a salt that commonly occurs with sodium or potassium. Traditionally it was used in the manufacture of gunpowder and munitions where it was originally extracted from urine and was then mined. Today nitrates are also employed as a source of nitrogen in inorganic fertilizers. Nitrate is limited in drinking water by the US EPA to a maximum of 10 mg/L when measured in units of nitrogen. The particularly susceptible group is infants below the age of six months.This is because the very young digestive tract hasn’t yet matured to handle levels above 10 mg/L, and the amount of water they consume is proportionally higher for their body weight. The infant may be exposed to nitrate when given a bottle of drinking water or reconstituted formula. Nitrate binds to the methemoglobin molecule that carries oxygen in the blood stream, making that oxygen unavailable. As a result, the baby’s skin and lips can turn bluish, the child can appear short of breath, and might be either fussy or listless. The illness is called methemoglobinemia or “blue baby syndrome.” There is as yet insufficient evidence to support an association with drinking water nitrate and birth defects, miscarriage, or harm to adults.

Sources of excess nitrate in drinking water are typically the runoff of agricultural fertilizers or manure and leaching from septic tanks. It is more likely to be found in shallow ground water sources. Municipalities must monitor and treat as necessary to meet the US EPA regulatory limit, therefore private water supplies are normally at greater risk of nitrate contamination. Nitrate in drinking water can be treated effectively by reverse osmosis, distillation, or a tank of nitrate-selective ion exchange resin – expert help is needed to ensure the technology being considered is appropriate for a particular situation. Prevention is an important option. For example, when considering digging a new well, determine whether it will be deep enough and far enough away from feedlot drainage and septic systems to prevent the well water quality from being influenced. Last, because of the potential sources of nitrate, it may be appropriate to test for fecal coliform bacterial contamination as well.

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Water Contaminant: Arsenic

by Mark B Published 5.1.2014

Arsenic is a metalloid element that has traditionally been useful in a broad range of applications due to its toxicity. Its occurrence in drinking water is undesirable for the same reason. Arsenic in groundwater is typically associated with deposits found in geologic formations. Leached into drinking water, it has been associated with a wide range of health effects that include lower intelligence in children, cancers, keratosis, and endocrine disruption. Arsenic can cross the placental membrane to reach the fetus. In 2001 the US EPA set the regulatory limit in public water supplies at 10 μg/L, although hundreds of small water systems remain out of compliance. The World Health Organization and Health Canada both have a Guideline value of 10 μg/L.

Inorganic arsenic is currently considered to be of greater concern to human health than the organic forms. Inorganic arsenic may be in the form of either trivalent arsenite or pentavalent arsenate. The former is more toxic and more challenging to remove due to the low proportion of ionic charge at drinking water pH. Arsenite is easily oxidized to arsenate with sodium hypochlorite, gaseous chlorine, permanganate, and ozone. It is less readily oxidized by chloramination, chlorine dioxide, contact with air, and either 254 nm UV light or hydrogen peroxide by themselves.

Periodic table cell for Arsenic

Arsenic can be treated at the household level whether the water is from the municipality or from a domestic source. It first needs to be measured for concentration and ideally, arsenic species, so that an appropriate treatment can be provided. Test kits are available that can be used, with some practice, to determine concentration of total arsenic. Speciation is probably best performed on site by a professional prior to submission to a laboratory for analysis.

It is unclear whether arsenic enters the body only by consuming it or by transdermal means as well. To treat the whole house (point-of-entry, or POE), a number of granular adsorbent media are available with varying effectiveness depending on species, pH, and interfering ions in the water. Some media claim to be effective on both arsenite and arsenate, though they may be more expensive. Often a low cost media, such as an iron-doped activated alumina, can be used economically in conjunction with a hypochlorite feed. A lead-lag tank system is often employed to allow monitoring of the beds as they deplete and thereby facilitate bed replacement prior to breakthrough. Depending on available space and the amount of naturally occurring iron consistently found in the source water, another practical POE alternative may be to oxidize both iron and arsenic, then filter out the co-precipitated floc with a bed of backwashable media. A rule of thumb is that a minimum ratio of 20:1 iron to arsenic is needed to consider this option. Reverse osmosis and distillation may be used for point-of-use (POU) applications. Higher arsenic concentrations can potentially be addressed with a post-membrane polishing cartridge for POU reverse osmosis. Ideally, systems being considered will be certified to ANSI/NSF Standards 53, 58, or 62 for arsenic reduction, or proven by some other third-party means such as the EPA’s programs for Environmental Technology Verification or Arsenic Demonstration. Regardless, regular monitoring is an important facet to any process for the reduction of arsenic in drinking water.

This is a contaminant which requires professional involvement for assessment, treatment, and maintenance to assure long term effectiveness.

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How does hard water affect my coffee and tea?

by Mark B Published 12.11.2013

A cup of tea or coffee is 99% water, so the water used for brewing makes a big difference in the quality of what you drink. There are hundreds of compounds that are released when hot water hits the beans and leaves. When we taste, we actually use both the tongue and the nose to create a complete picture. (Just try eating soup with one hand pinching your nose…it won’t taste the same.) So if the water isn’t especially good, it can rob you of what should be a pleasurable break—chlorine and hardness are major culprits.

Chlorine will attack the flavor compounds and may be strong enough to compete with the aroma from the cup. A good carbon filter is all that’s needed to eliminate this bad actor from your diet, and the rest of your drinking water will taste better too.

Hardness is typically Calcium and Magnesium and maybe a little Iron that’s dissolved in your water. (Learn more about hardness or iron). When these minerals combine with compounds in tea and coffee, they bind together to form solids. Flavors and aroma are tied up and taken away from your mouth and nose. A water softener and/or reverse osmosis system are effective ways to fix this problem. My personal preference is an RO system, because it has a carbon filter for the chlorine, a membrane to purify, and a mineral cartridge polisher to ensure a complementary balance of ions for the tea and coffee to steep in.

Here’s something you can try just for fun if you have hard water at home or work. It also makes a simple, but safe and effective science fair project. Buy a bottle of water at the supermarket, making sure to pick one that’s been treated by reverse osmosis. Brew two cups of tea at the same time in the microwave: one with hard water, and the other with RO water. About 90 seconds should do it. Take the cups out of the microwave and remove the teabags. Now compare color; is one muddier than the other? Smell and taste; the cup made with RO water will be brighter and livelier on the palate, and you may also detect a cleaner flavor. It’s easy to observe that just because a cup of tea is darker does not mean it is stronger or richer, or that is has a full range of flavors for you to enjoy.

I did this “tea test” with a standard bag of Lipton black tea and then took these photos.

Top view of the tea test results Side view of tea test results: RO waterSide view of tea test results: hard water

Can you guess which is which?

The tea made with RO water was, you guessed it, the one on the left. I chose a black tea (instead of a green or white) because I thought the result to be visually more striking. Doing this with a highly aromatic tea such as orange pekoe, or a more subtle green tea also demonstrates what a profound difference the right water makes.

Life is just too short for a bad cup.

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Using Our Oceans to Produce Drinking Water

by Mark B Published 4.2.2013

Learning to SCUBA dive at an early age in the chilly Gulf of Maine gave me exciting views of an incredible hidden world. This led to other adventures exploring the salty world beneath the waves, researching whales, coral reefs and fisheries. On one of these occasions I spent about six months on a tall ship, where our drinking water was taken from the ocean and filtered by a specialized, high pressure, reverse osmosis (RO) membrane. The RO takes in sea water and rejects the salts, leaving fairly pure, fresh water. People can’t drink sea water directly because it puts the body’s natural balance of salts out of whack—there’s so much salt in sea water that it actually drives the water out of our bodies. Not so good when you’re thirsty. I’m reminded of a line from an old poem, the Rime of the Ancient Mariner, where a sailor and his boat were trapped far from land: “Water, water every where Nor any drop to drink.”

It’s incredible that the oceans hold over 97% of all the water on our planet. The remaining is fresh water, most of which is locked up in the polar ice caps and permanent ice on mountains; less than 1% of the Earth’s water is potentially available for drinking. If you filled a five gallon bucket and said that it represents all the water on our planet, nearly all of it would be too salty to drink. In fact, roughly ½ a cup from that whole bucket would represent all that we have in the ground, our lakes, rivers, and ponds. Consider that even less than that is easy to make safe for drinking—not so muddy, brackish or polluted that extra measures are needed. Unfortunately, there are many places where people can’t afford to treat the water and end up drinking it as-is, contaminants and all. The worse the water quality is, the harder we have to work to make our tiny existing fresh water supplies drinkable.

This means, for those who can afford treatment, we put in energy, equipment, disinfection chemicals, time and effort to make it potable. Is all that water in our oceans unavailable to us, like it was for the Ancient Mariner? Like on my ship, when it comes to salts, high pressure RO membranes are now used for many communities around the world (including here in the United States) to make drinkable water from the oceans. Another common way to do this is distillation. These are important technologies for areas with access to salty water but not enough fresh and as you may have guessed they do require significant energy inputs. 

Image of DewPoint Systems' RainDome

Image courtesy of DewPoint Systems.

Another interesting technology, DewPoint Systems' RainDome,uses naturally cool sea water to draw moisture from the air without electricity or moving parts. In coastal areas where the conditions are right, the fresh water it makes can be used for drinking and even to irrigate crops.Using the oceans to produce drinking water is not only possible, increasingly, it’s a reality for a thirsty world.

Want to learn more? Check out the following resources.

Desalination by Reverse Osmosis:

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How Do You Use Water?

by Mark B Published 9.11.2012

We use water in so many ways, just around the house. For most of us, it’s always there – just turn the faucet handle and get instant gratification along with the wet stuff. Lose that water from a power outage or a break in the water main and we very quickly remember how incredibly important it is. My own appreciation list is a long one – I use it to: drink for health and hydration, provide to pets and houseplants, wash dishes, fruit and veggies, my body, clothes, and the car, flush the toilet, and to brush teeth. What’s on your list? In these days of increasing water scarcity, it pays to ensure the supply of clean waters lasts as long as it can. It’s not free, and making water clean enough to use costs extra - conservation helps the wallet now and leaves more for the future.

Piggy bank with a tap coming out of itOne way to cut back is to replace older appliances with ones that limit the amount of water that gets used each time. Last year when our washing machine finally broke beyond my ability to fix it yet again, I replaced it with a high efficiency front loader. As much as I hate putting things into the landfill before their time, I really might have thought to do this earlier: not only is the electrical cost cut to less than half, it uses about one third the water without sacrificing how clean the clothes get. I pay a lot for my water (and electricity), so that’s a pretty sweet deal.

One study found American homes have around 11 toilet flushes per day (Rockaway et at, 2011). Where the older toilets may use 3.5 gallons per flush (gpf), a water conserving toilet uses just 1.6 gpf, saving about 7,600 gallons a year in that household. That’s a lot of water! I replaced the toilets when we moved into our house not too long ago, but I hadn’t realized until just now how much this has impacted our water usage and the utility bills.

A few other useful things we can do include:

• Install low flow shower heads and faucets. These don’t reduce the pressure of the water coming out so it should still feel like it’s at full force, but the volume is limited.

• Consider watering the lawn only when needed instead of using a timer. Those with irrigation systems can save water by using a sensor to control when it turns on based on the weather or how dry the soil actually is. • Use a soaker hose or drip emitters to water just the outdoor plants you want to target.

• If you feel you have to use chemicals on the lawn or farm, follow the directions scrupulously to reduce how much ends up in the environment or even back in your drinking water. That should help keep down the cost of treating your water to make it safe to drink. And when pollutants are removed, a fair amount of water can be used to carry them away, so less contamination can means less wasted water too.

How do you use water? For just a day, try to be conscious of each time you open a faucet, do a load of laundry, or flush the toilet. What would it be like to do without? There are some fairly easy ways to reduce, saving both water and money. The more we save today, the more there is tomorrow.

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Water: Understand it, Value it, Respect it. Learn more about life’s most vital resource.

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